Auto merge of #18003 - DarkDrek:move_percentage, r=canaltinova

Move percentage to mod.rs

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The tests in the issue worked for me locally.

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- [ ] `./mach build -d` does not report any errors
- [ ] `./mach test-tidy` does not report any errors
- [X] These changes fix #18001 (github issue number if applicable).

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- [X] These changes do not require tests because they are just refactoring

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components/style/properties/gecko.mako.rs

@@ -62,9 +62,8 @@ use std::mem::{forget, uninitialized, transmute, zeroed};
 use std::{cmp, ops, ptr};
 use stylesheets::{MallocSizeOfWithRepeats, SizeOfState};
 use values::{self, Auto, CustomIdent, Either, KeyframesName};
-use values::computed::{NonNegativeAu, ToComputedValue};
+use values::computed::{NonNegativeAu, ToComputedValue, Percentage};
 use values::computed::effects::{BoxShadow, Filter, SimpleShadow};
-use values::computed::length::Percentage;
 use computed_values::border_style;
 
 pub mod style_structs {